With reference to FIG. 1, a high pressure compressor of a modern turbomachine used in aeronautics for the propulsion of aircraft includes a stator 2 and a rotor 8 rotating around the main axis 4 of the turbomachine. The first stages 3 of these axial compressors are equipped with stator blades 1 with a variable phase angle. In fact, these rectifiers are mounted rotating in bushes 13 fixed to the stator 2. In other words, the orientation of these stator blades around an axis perpendicular and intersecting with the spin axis 5 of the rotor 8 is adjustable during operation. Thus, for each stator blades 1, there is a crank 7 mounted for pivoting around the spin axis 10 of each rectifier 1. The pivoting of each of these cranks 7 obtained by means of control means 11 allows for adjustment of the phase angle of each of the stator blades 1.
The search for improved performances of these turbomachines concerns efficiency and obtaining a maximum thrust. This search has rendered these motors extremely sensitive as regards their thermic state. So as to reduce this sensitivity, particular attention is paid to secondary phenomena appearing during functioning of the machine. One particular phenomenon is leaking or an imperviousness defect and this has led to finding a way to fully control play on functioning between the fixed portions (for example, the stator blades) and the rotating portions (such as the rotor). These problems are encountered more particularly between the extremity of the stator blades and the external portion of the rotor of the compressor which is sometimes equipped with an imperviousness system commonly known as a "licking" system.
French patent No. 2 603 340 describes a turbomachine comprising a device for adjusting the play of a labyrinth gasket intervening between the rotor and the stator of a compressor so as to obtain an alignment of the main vein of the gases flowing inside the compressor. This system acts at the end of the stator blade whose phase angle is adjustable. On the other hand, this play adjustment device is independent of the phase adjustment.
The present invention is able to accurately and automatically adjust the radial play between the stator blade and the rotor of the compressor during functioning of the turbomachine.